• 제목/요약/키워드: Solar Thermal Power Plant

검색결과 50건 처리시간 0.025초

반사거울 설치 방향 조정에 의한 Heliostat 기구오차에서 기인하는 태양추적오차의 보정 (Compensation of Sun Tracking Error caused by the Heliostat Geometrical Error through the Canting of Heliostat Mirror Facets)

  • 박영칠
    • 한국태양에너지학회 논문집
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    • 제29권6호
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    • pp.22-31
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    • 2009
  • Canting is the optical alignment of mirror facets of heliostat such that the heliostat could focus the energy as a unit concentrator. Canting could improve the optical performance of heliostat and thus improves the efficiency of heliostat and ultimately improves the efficiency of the solar thermal power plant. This study discusses the effect of mirror canting, especially off-axis canting, used to compensate the sun tracking error caused by the heliostat geometrical errors. We first show that the canting could compensate the sun tracking error caused by the heliostat geometrical errors. Then we show that the proper canting time could exist, depending on the heliostat location. Finally we show how much the sun tracking performance could be improved by canting, by providing RMS sun tracking error. The limitation and caution of using canting to improve the sun tracking performance are also discussed.

한국형 지열발전 타당성 연구 (A Feasibility Study on Geothermal Power Plant in Korea)

  • 임효재;권정태;김금수;장기창
    • 대한설비공학회:학술대회논문집
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    • 대한설비공학회 2009년도 하계학술발표대회 논문집
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    • pp.39-44
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    • 2009
  • Geothermal energy is the heat contained in the earth and its internal fluids. Geothermal energy is stored as sensible or latent heat. Supplied by both internal and external sources, it represents a vast supply which is only started to be tapped for generation of electric power. In general, this is natural dry or wet medium to high enthalpy steam at temperatures above $150^{\circ}C$. For some time, binary systems employing substances with a lower boiling point than water in a secondary circuit have been used to generate vapor for driving turbines at a lower temperature level. The utilization of binary plants and the possibility of production from enhanced geothermal systems can expand its availability on a worldwide basis. The geothermal electricity installed capacity is approaching the 10,000GW threshold. Geothermal energy is not present everywhere, but its baseload capability is a very important factor for its success.

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Kalina 사이클의 효율 향상 방안 및 성능 비교 (Improvement of Efficiency of Kalina Cycle and Performance Comparison)

  • 윤정인;손창효;최광환;손창민;설성훈;이호생;김현주
    • 한국태양에너지학회 논문집
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    • 제35권5호
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    • pp.11-19
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    • 2015
  • In this paper, EP-Kalina cycle applying liquid-vapor ejector and motive pump is newly proposed. In this EP-Kalina cycle, the liquid-vapor ejector is used to increase pressure difference between inlet and outlet of the turbine. Also the motive pump enhances the performance of liquid-vapor ejector, resulting in increase of system efficiency of OTEC cycles. The comparison cycles in this study are basic, Kalina, EKalina and EP-Kalina ones. The pump work, net power, APRe, APRc, TPP and system efficiency of each cycle are compared. In case of net power, EP-Kalina cycle is lowest among the cycles due to the application of the motive pump. But, the net power difference of cycles seems to be minor since the pump work of cycles is merely about 1kW, compared to turbine gross power of 20kW. The system efficiency of EP-Kalina cycle shows 3.22%, relatively 44% higher than that of basic OTEC cycle. Therefore, the system efficiency is increased by applying the liquid-vapor ejector and the motive pump. Additional performance analysis is necessary to optimize the proposed EP-Kalina cycle.

경제성분석 프로그램을 이용한 도심형 마이크로그리드 최적 설계 (Optimal Design of Urban MICROGRID using Economical Analysis Program)

  • 유승덕;임성우;임유석;황성욱;이학주
    • KEPCO Journal on Electric Power and Energy
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    • 제8권2호
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    • pp.69-72
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    • 2022
  • This paper actually investigates the load on major large-scale buildings in the downtown area, examines the economic feasibility of installing PV and ESS in a microgrid target building, and evaluates whether an electric vehicle capable of V2G through two buildings is effective as an economical analysis program (HOMER) was analyzed using. It is economical to install a mixture of ESS rather than using the whole PV, and it is shown that if there is an electric vehicle using the V2G function of EV, there is an economic effect to replace the PV. So that Incentives and policies are needed to replace a large area of PV and utilize the existing parking lot to lead EV as a resource of the microgrid. Currently, P2X technology that stores power as ESS or converts it to other energy to control when surplus renewable energy occurs in large-capacity solar power plants and wind farms, etc. This is being applied, and efforts are being made to maintain the stability of the system through the management of surplus power, such as replacing thermal energy through a heat pump. Due to the increase in electric vehicles, which were recognized only as a means of transportation, technologies for using electric vehicles are developing. Accordingly, existing gas stations do not only supply traditional chemical fuels, but electricity, and super stations that also produce electricity have appeared. Super Station is a new concept power plant that can produce and store electricity using solar power, ESS, V2G, and P2G. To take advantage of this, research on an urban microgrid that forms an independent system by tying a large building and several buildings together and supplies power through a super station around the microgrid is in full swing.

미활용 열에너지를 이용한 바이너리 발전과 신경망 제어 (Binary Power plant using unused thermal energy and Neural Network Controllers)

  • 한건영;박성대
    • 한국정보통신학회논문지
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    • 제25권10호
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    • pp.1302-1309
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    • 2021
  • 최근, 정부는 경기침체 극복에 대응하고 구조적 변환에 따른 국제활동을 주도하기 위한 국가발전 전략으로 "한국판 뉴딜 종합계획"을 도입하였다. 한국판 뉴딜에서 에너지와 관련된 '그린뉴딜'은 배출 가스 제로화를 목표로 하고 저탄소 녹색 경제로의 전환을 가속화하는 것이며, 이를 위해 정부는 재생에너지 사용 확대를 촉진한다는 계획이다. 본 논문에서는 저탄소 녹색 경제로의 전환을 촉진하기 위해 미활용 저온 열에너지를 활용하는 바이너리 발전과 실제 발전환경에서 무인 자동운전을 통해 저 비용으로 유지관리가 가능한 신경망 기반 제어시스템에 대해 검토한다. 이러한 바이너리 발전의 실현은 태양광, 풍력 등과 더불어 재생에너지의 도입을 가속화 할 것으로 기대된다.

증기-증기 이젝터를 적용한 OTEC 시스템 성능의 수치적 분석 (The numerical analysis of performance of OTEC system with vapor-vapor ejector)

  • 윤정인;손창효;예병효;하수정;최인수;이호생;김현주
    • 한국태양에너지학회 논문집
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    • 제34권4호
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    • pp.45-50
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    • 2014
  • In this paper, the Ocean Thermal Energy Conversion(OTEC) with vapor-vapor ejector is proposed newly. At this OTEC system, a vapor-vapor ejector is installed at inlet of condenser. The vapor-vapor ejector plays a very important role in increasing of the production work of low-stage turbine throughout the decrement of outlet pressure of ejector. The performance analysis is conducted for optimizing the system with HYSYS program. The procedure of performance analysis consists of outlet pressure of high turbine, the mass ratio of working fluid at separator, total working fluid rate, and nozzle diameters of vapor-vapor ejector. The main results is summarized as follows. The nozzle diameter is most important thing in this study. When each nozzle diameter of vapor-vapor ejector is 10 mm, the efficiency of OTEC system with vapor-vapor ejector shows the highest value. So it is necessary to set the optimized nozzle diameters of vapor-vapor ejector for achieving the high efficiency OTEC power system.

폐쇄형 해양온도차발전 사이클에 관한 연구 (A Study of Closed OTEC Power Plants)

  • 신상호;정동수;김종보;서태범;천원기;오정무
    • 태양에너지
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    • 제17권4호
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    • pp.23-33
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    • 1997
  • 본 연구에서는 Rankine 사이클을 이용한 해양 온도차 발전 시스템을 컴퓨터로 모사했고 작동유체를 변화시켜 가면서 그 성능을 비교하였다. 증발기와 응축기는 UA(총괄열전달계수$\times$전열면적)와 LMTD(대수평균온도차) 방법으로 모사하였으며 터빈과 펌프는 등엔트로피 효율로 모사하였다. 작동유체로는 R22, R290, R1270, R134a, R125, R143a, R32, R410A 그리고 암모니아 등을 사용하였다. 모사 결과 OTEC 발전 시스템의 효율은 작동유체에 상관없이 거의 일정한 것으로 드러났다. 한편 증발기 출구에서의 과열도와 응축기 출구에서의 과냉도는 시스템의 성능에 거의 영향을 미치지 않는 것으로 나타났지만 터빈의 효율과 열교환기의 크기는 시스템 성능에 큰 영향을 미치는 것으로 나타났다. 마지막으로 따뜻한 표층수와 차가운 심해수 사이의 온도차가 $20^{\circ}C$이상일 때 실제로 전기를 생산할 수 있다는 사실을 확인했다.

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설비공학 분야의 최근 연구 동향 : 2010년 학회지 논문에 대한 종합적 고찰 (Recent Progress in Air-Conditioning and Refrigeration Research : A Review of Papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2010)

  • 한화택;이대영;김서영;최종민;김수민;권영철;백용규
    • 설비공학논문집
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    • 제23권6호
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    • pp.449-469
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    • 2011
  • This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigerating Engineering during 2010. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) Research trends of thermal and fluid engineering have been surveyed as groups of general thermal and fluid flow, fluid machinery, and new and renewable energy. Various topics were presented in the field of general thermal and fluid flow. Research issues mainly focused on the thermal reliability of axial fan and compressor in the field of fluid machinery. Studies on the design of ground source heat pump systems and solar chemical reactors were executed in the field of new and renewable energy. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics and industrial heat exchangers. Researches on heat transfer characteristics included heat transfer in thermoelectric cooling/power generation systems, combined heat and power systems, carbon nano fluid with PVP, channel filled with metal foam and smoke ventilation in a rescue station of a railroad tunnel. Also the studies on flow boiling of R123/oil mixture in a plain tube bundle and R410A charge amount in an air cooled mini-channel condenser were reported. In the area of industrial heat exchangers, researches on plate heat exchanger, shell and tube heat exchanger, enthalpy exchanger, micro channel PCHE were performed. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics and industrial heat exchangers. Researches on heat transfer characteristics included heat transfer in thermoelectric cooling/power generation systems, combined heat and power systems, carbon nano fluid with PVP, channel filled with metal foam and smoke ventilation in a rescue station of a railroad tunnel. Also the studies on flow boiling of R123/oil mixture in a plain tube bundle and R410A charge amount in an air cooled mini-channel condenser were reported. In the area of industrial heat exchangers, researches on plate heat exchanger, shell and tube heat exchanger, enthalpy exchanger, micro channel PCHE were performed. (3) Refrigeration systems with alternative refrigerants such as hydrocarbons, mixed refrigerants, and CO2 were studied. Performance improvement of refrigeration systems are tried applying various ideas of refrigerant subcooling, dual evaporator with hot gas bypass control and feedforward control. The hybrid solar systems combining the solar collection devices with absorption chillers or compression heat pumps are simulated and studied experimentally as well to improve the understanding and the feasibility for actual applications. (4) Research trend in the field of mechanical building facilities has been found to be mainly focused on field applications rather than performance improvements. Various studies on heating and cooling systems, HVAC facilities, indoor air environments and energy resources were carried to improve the maintenance and management of building service equipments. In the field of heating and cooling systems, papers on a transformer cooling system, a combined heat and power, a slab thermal storage and a heat pump were reported. In the field of HVAC facilities, papers on a cooling load, an ondol and a drying were presented. Also, studies on HVAC systems using unutilized indoor air environments and energy resources such as air curtains, bioviolence, cleanrooms, ventilation, district heating, landfill gas were studied. (5) In the field of architectural environment and energy, studies of various purposes were conducted such as indoor environment, building energy, renewable energy and green building. In particular, renewable energy and building energy-related researches have mainly been studied reflecting the global interest. In addition, many researches which related the domestic green building certification of school building were performed to improve the indoor environment of school.

설비공학 분야의 최근 연구 동향: 2014년 학회지 논문에 대한 종합적 고찰 (Recent Progress in Air-Conditioning and Refrigeration Research: A Review of Papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2014)

  • 이대영;김사량;김현정;김동선;박준석;임병찬
    • 설비공학논문집
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    • 제27권7호
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    • pp.380-394
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    • 2015
  • This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2014. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) The research works on the thermal and fluid engineering have been reviewed as groups of heat and mass transfer, cooling and heating, and air-conditioning, the flow inside building rooms, and smoke control on fire. Research issues dealing with duct and pipe were reduced, but flows inside building rooms, and smoke controls were newly added in thermal and fluid engineering research area. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics, pool boiling and condensing heat transfer and industrial heat exchangers. Researches on heat transfer characteristics included the results for thermal contact resistance measurement of metal interface, a fan coil with an oval-type heat exchanger, fouling characteristics of plate heat exchangers, effect of rib pitch in a two wall divergent channel, semi-empirical analysis in vertical mesoscale tubes, an integrated drying machine, microscale surface wrinkles, brazed plate heat exchangers, numerical analysis in printed circuit heat exchanger. In the area of pool boiling and condensing, non-uniform air flow, PCM applied thermal storage wall system, a new wavy cylindrical shape capsule, and HFC32/HFC152a mixtures on enhanced tubes, were actively studied. In the area of industrial heat exchangers, researches on solar water storage tank, effective design on the inserting part of refrigerator door gasket, impact of different boundary conditions in generating g-function, various construction of SCW type ground heat exchanger and a heat pump for closed cooling water heat recovery were performed. (3) In the field of refrigeration, various studies were carried out in the categories of refrigeration cycle, alternative refrigeration and modelling and controls including energy recoveries from industrial boilers and vehicles, improvement of dehumidification systems, novel defrost systems, fault diagnosis and optimum controls for heat pump systems. It is particularly notable that a substantial number of studies were dedicated for the development of air-conditioning and power recovery systems for electric vehicles in this year. (4) In building mechanical system research fields, seventeen studies were reported for achieving effective design of the mechanical systems, and also for maximizing the energy efficiency of buildings. The topics of the studies included energy performance, HVAC system, ventilation, and renewable energies, piping in the buildings. Proposed designs, performance performance tests using numerical methods and experiments provide useful information and key data which can improve the energy efficiency of the buildings. (5) The field of architectural environment was mostly focused on indoor environment and building energy. The main researches of indoor environment were related to the evaluation of work noise in tunnel construction and the simulation and development of a light-shelf system. The subjects of building energy were worked on the energy saving of office building applied with window blind and phase change material(PCM), a method of existing building energy simulation using energy audit data, the estimation of thermal consumption unit of apartment building and its case studies, dynamic window performance, a writing method of energy consumption report and energy estimation of apartment building using district heating system. The remained studies were related to the improvement of architectural engineering education system for plant engineering industry, estimating cooling and heating degree days for variable base temperature, a prediction method of underground temperature, the comfort control algorithm of car air conditioner, the smoke control performance evaluation of high-rise building, evaluation of thermal energy systems of bio safety laboratory and a development of measuring device of solar heat gain coefficient of fenestration system.

초임계 CO2 발전 기술개발 동향 (The Technology Development Trends of Supercritical CO2 Power Generation)

  • 김범주
    • KEPCO Journal on Electric Power and Energy
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    • 제2권4호
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    • pp.531-536
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    • 2016
  • 세계적으로 온실가스저감에 대한 요구가 높아지고 있는 가운데 고효율 발전 시스템의 개발에 대한 연구개발이 꾸준히 진행되고 있다. 초임계 $CO_2$ 발전기술은 효율 향상과 소형화, 다양성의 장점을 가지고 있어, 2000년대 이후 세계 여러 나라에서 연구개발에 박차를 가하고 있다. 초임계 $CO_2$ 발전 시스템은 $CO_2$를 작동유체로 하는 발전 시스템으로 크게 간접가열방식과 직접가열방식으로 구분될 수 있다. 현재, 대부분의 연구는 간접가열방식의 초임계 $CO_2$ 발전 시스템 개발에 집중되어 있고, 미국은 NREL을 중심으로 태양열 연계 초임계 $CO_2$ 발전 시스템을 개발 중이며, DOE는 올 해 화력 연계 초임계 $CO_2$ 발전 시스템 개발에 대한 투자도 시작할 계획이다. GE는 10MW급 초임계 $CO_2$ 발전 시스템 개발뿐만 아니라, 50MW급과 450MW급 초임계 $CO_2$ 발전시스템의 개념 설계도 진행 중에 있다. 우리 나라에서는 원자력연구원이 초임계 $CO_2$ 발전시험 설비를 구축해오고 있으며, 한국전력공사 전력연구원은 현대중공업과 함께 디젤 및 가스엔진 폐열을 이용하여 2MW급 초임계 $CO_2$ 발전시스템 개발을 진행 중에 있다.